Stopblocks ensure consistent dado cuts
Measure carefully and clamp two separate blocks (A and B in the drawing above) to the top of your tablesaw to establish the right- and left-hand limits of the dado. Position the stock against stopblock A, make the cut, and do likewise after aligning the stock with block B. Use scrap stock to check your settings before cutting the actual workpieces, and hold the stock securely against the miter gauge.
—Silvia Eder, Rio de Janeiro, Brazil